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GNOME Shell extension providing a countdown timer in the top panel

Installing this package adds a timer application to the GNOME Shell top panel.
With it you can start a timer of any duration and when elapsed, you'll get a
notification. You can also preconfigure various durations to avoid having
to retype them.

It's a natural replacement of the "timer applet" for GNOME 2 (or 3 in
fallback mode).